Preheat oven to 350 degrees F (175 degrees C). Grease a 9-inch pie plate.
Beat egg whites in a glass or metal bowl until foamy. Gradually add 1 cup sugar and baking powder, continuing to beat until soft peaks form. Lift your beater or whisk straight up: the egg whites will form soft mounds rather than a sharp peak.
Fold crackers and pecans into the egg whites. Add vanilla and stir.
Bake pie in preheated oven until set in the middle, about 30 minutes. Set aside to cool to room temperature.
Beat cream with pinch sugar in a bowl until stiff peaks form. Lift your beater or whisk straight up: the cream will form sharp peaks. Top cooled pie with whipped cream to serve.
